Southern Elephant Seals

Animal-mounted instrumentation provides researchers with new insight into the relationship between oceanographic conditions and southern elephant seal behavior and distribution.

The distribution and movements of large marine predators in relation to oceanographic conditions is critical to deepening our understanding of their ecology and for potential conservation and management efforts. However, up until now, it has been virtually impossible for researchers to directly observe how the behaviors of these animals may vary according to site specific environmental conditions. Census of Marine Life researchers, as part of the larger Southern Elephant Seals as Oceanographic Samplers (SEaOS) program, are now changing this by utilizing the novel approach of tagging marine life with sensors that can detect and relay specific environmental data as well as location information.

By tagging southern elephant seals with satellite telemetry tracking tags that also contain sensors to detect such oceanographic conditions as temperature, salinity, and depth, researchers from SEaOS have been able to correlate the movements of these animals with localized environmental conditions. By following the movements of these seals and analyzing the oceanographic data collected by the sensors they are carrying, researchers have begun to explain the distribution patterns of elephant seals and their migration behavior. Results for some seal groups reveal behaviors such as consistent diving to depths providing warmer water. This correlates with potential over-wintering habitat for possible prey species, suggesting that even though the seals spent a lot of time in near freezing surface water conditions, they dove to warmer depths to forage. Other results showed a correlation between the buoyancy (explained as an indicator of feeding success due to increased body fat levels) of the seal and the area in which it moved. This enabled researchers to attempt to explain certain migration patterns.

Satellite telemetry tracking technology represents a powerful tool with which to investigate the ecology of these large marine animals and to explain their migrations and behaviors by providing data that gives researchers detailed insight into habitat choice. As the permanent ice shelves of Antarctica shrink, a firm understanding of the environmental requirements of these and other animals is imperative. The further development of this technology may provide an unprecedented ability to explain and predict the response of animals to climate change and environmental variability and aid future conservation and management efforts.

Research Location: Circumpolar seas in the Ocean around the continent of Antarctica.

What: Animal-mounted instrumentation provides researchers with new insight into the relationship between oceanographic conditions and southern elephant seal behavior and distribution.